Apple Cider

A customer arrives at an apple cider farm with a five gallon container and asks the farmer to put four gallons of his finest cider into it. Unfortunately, the only measure the farmer has is a three gallon jug. Can you think of a way that the farmer can measure out exactly four gallons of cider using just these two containers?

Answer

First, fill up the three gallon jug. Pour the three gallons into the five gallon container. Refill the three gallon jug and once again pour it into the five gallon container until it is full. The three gallon jug now contains one gallon. Empty the five gallon container back into the storage tank and then pour the one gallon of cider into it. Now, fill the three gallon jug up again and pour it into the customer`s five gallon container. The container will now contain the desired four gallons.Hide